食品中胆固醇含量测定方法的研究与比较

The Determination of the Cholesterol Concentration in the Food Product and the Study of the Method

胆固醇存在于动物的所有组织中,是动物体维持正常生理活动所必需的。但人体内过多的胆固醇将引起高血脂,并进而引发一系列心血管疾病,所以我们要控制饮食中胆固醇的摄入,因此检测食品中胆固醇的含量,确立一种快速、准确的胆固醇含量的测定方法是十分必要的。本文采用比色法测定。该法样品微量,无需提取脂质,用直接皂化法即可。这样不仅避免用毒性大而昂贵的试剂,且操作时间大大缩短。通过充入氮气,加入三氟化硼乙醚,更加促进了整个皂化过程的完全。由正交试验选择出了最佳前处理条件。其测定结果的精密度高,变异系数为1.33%。回收率(83.0%～89.0%)也较满意,测定值13.717mg/g与传统比色法测定值13.382mg/g相比有良好的一致性。本文除对蛋黄中胆固醇含量进行测定外,还对部分水产品进行了测定。测定结果否定了鱿鱼中胆固醇含量很高的推论,说明这些胆固醇几乎完全存在于鱿鱼内脏里,人们食用鱿鱼不必顾虑胆固醇过高。测定结果表明本方法也适用于其它样品的测定。

Cholesterol exists in all the tissue of the animals,and it's essential for the animals to maintain their normal physiologicbehavior.But the surplus cholesterol in human body will leads to high blood cholesterol level and furthermore results in a seriesof vascular disease,so we should control the dietary intake of the cholesterol,and therefore it is greatly necessary to determine thecholesterol concentration in the food product in order to settle a precise determination method of the cholesterol concentration.The colormetric method is used in this paper.The micro-amount of the sample is used in this method,which doesn't need to extractthe lipid and just uses the direct saponofication method,thus using this method not only avoids using the mosttoxic andexpensive material but also reduces the time of the operation significantly,this method can promote the completion of the wholesaponification proceeding by the addition of nitrogen gas and Boron Trifluoride Etherate.The best saponification conditions arechosen out by the orthogonal experiment.The results measured has a high precision value.The variation coefficient is 1.32%,therecovery ratio which 84.0%～89.7% makes the researchers satisfied.In the paper parts of seafoods are analyzed,except thedetermination of the cholesterol concentration in the egg yolk.The results of the determination denis that there is high cholesterollevel in squids,and shows that the cholesterol nearly exists in the internalorgans of the squids,when people eat them,they needn'tconsider surplus intake of the cholesterol.Finally the consequence of this experiment shows this method also adapt to thedetermination of other samples.